--%>

Problem on work of compression

A diesel engine operates devoid of a spark plug by using the high-temperature gas produced throughout the compression stage to ignite the fuel. During a typical compression, pure air that is originally at 21 °C and 0.95 bar is reversibly and adiabatically compressed to 1/20 of its original(actual) volume by the piston, as shown in the figure below.

a) If air is assumed to obey the ideal gas equation of state, find out the pressure and temperature in the cylinder at the end of the compression. The constant-pressure heat capacity of air varies with temperature and is given by

Cp/R = 3.3 + 6x10-4

b) What is the work of compression in J/mol of air?

c) Is the ideal gas law a good approximation in this case? Why?

2455_ideal gas law.jpg

   Related Questions in Mechanical Engineering

  • Q : Problem on motion of the system (a) A

    (a) A plane moving at a constant velocity, V, crashes into a building as shown in figure below. Due to the design against plane crash of that building, neither major damage nor explosion occurs but the building vibrates after the crash. Assuming that the building can

  • Q : Solution A pump station has been

    A pump station has been designed to lift water out of a 6 metre deep pit (vented to atmosphere) via a centrifigual pump mounted at ground level. Liquid conditions 20OC Suction pipe work losses 2.0 metres NPSH safety factor 5.0 kPa Vapor pressure @ 20oC 0.25 metres (a) Calculat

  • Q : Static and Dynamic load What are Static

    What are Static and Dynamic load and what are their significant dynamic effects?

  • Q : Problem on discharge of water In the

    In the below system, d = 6 in., D = 12 in., Δz1 = 6 ft, and Δz2 = 12 ft. The discharge of water in the given system is 10 cfs. Is the machine a turbine or a pump ? Determine the pressures at points A and B? Neglect head losses. Suppos

  • Q : Brazing and Welding Differentiate the

    Differentiate the term Brazing and Welding?

  • Q : Calculate the surface area available

    You are working in a company that has developed a process to produce DNA vaccines from E.coli. After the fermentation step a lysis step is used to release the DNA from the cells resulting in a sticky mixture. You find that an aggressive cleaning solution heated to 80°C is required to

  • Q : State Concurrent Engineering Concurrent

    Concurrent Engineering has happened primarily as a result of the need to shorten product development times, but improving product quality and reducing product life-cycle costs are important considerations. Some companies have even gone to the extent o

  • Q : Aim of an airspeed indicator in aircraft

    What is the main aim of an airspeed indicator in aircraft?

  • Q : Petroleum technology theories for the

    theories for the origin of petroleum, methods for detection of petroleum deposits, fractional distillation

  • Q : Free Vibration of MDOF Systems Why free

    Why free vibration takes place at MDOF system?